The hollow muscular organ, part of the digestive tract, is located between the esophagus and the duodenum. The stomach has a dilated structure and functions as a vital organ in the digestive system. The stomach is involved in the gastric phase of digestion, following chewing. It performs a chemical breakdown by means of enzymes and hydrochloric acid. The stomach secretes digestive enzymes and and gastric acid to aid in food digestion.